MIRI Imaging Target Acquisition
Target acquisition (TA) is generally not required for MIRI imaging observations, as the blind pointing ability of the telescope is sufficiently accurate to center the target in the imager field or subarray. For the special case of high precision photometry of bright sources, such as time-series observations (TSOs), TA may be desired.
See also: JWST Pointing Performance
The MIRI imager can be used to obtain high precision photometry of bright sources that may be useful for time-series observations (TSOs). Given the high stability and photometric precision required for such observations, target acquisition (TA) is usually recommended to ensure that the target is very accurately placed in the nominal pointing position for the required subarray. This is particularly important for repeated observations, where different exposures will be combined.
Target acquisition for MIRI imaging is currently not supported. The need for this capability is being explored based on commissioning results, but is not available in Cycle 3.